795 FXUS65 KPIH 091959 AFDPIH Area Forecast Discussion National Weather Service Pocatello ID 1259 PM MST Mon Jan 9 2023 .SHORT TERM...Tonight through Thu afternoon. In the middle of a moist and warm winter storm overhead. The central Idaho mountains are nearly halfway through their event, while it is just starting in the upper Snake and other eastern highlands. The same is true for the Snake River plain, where it should hover right around the freezing mark, making a messy rain and snow event, changing over late tonight to snow. Wind should increase in intensity from the south and southwest, but since it should be fairly wet for the lower elevations, may not see a strong impact on drifting and blowing, unless at high elevations in the passes. Western zones should wrap up tonight, with the eastern zones going until at least 10/18Z 1100AM tomorrow. A brief break will occur, but another low moving through northern UT will bring light accumulations in most locations, except light to moderate in the southern highlands where upslope aids the snow production. The surface northerly flow should keep things colder, along with the cloud cover in that area. Central Idaho mountains may receive some light snow, along with the upper Snake River highlands. This second storm arrives as early as the afternoon in the western zones again, then wraps up Tue afternoon for the most part. Light snow may continue through Wed afternoon in the eastern highlands from the MT border to the UT border. Wed evening through Thu afternoon should be precipitation free. Messick .LONG TERM...(Thu PM - next Monday)... Upper level ridge looks to be in place over the area Thursday and will gradually begin to break down by the time we get into the weekend. This will send the best moisture to the north of the region during this time but we could still see just enough for a few stray snow showers across the Central Mountains. Ridge begins to break down during the day Saturday as U/L trough again sets up across the Pac NW. This should allow moisture to gradually overspread the area once again on Sunday and into Monday bringing precip chances back into the forecast. Temperatures during this period will be in the mid 30s to lower 40s across the valleys while continuing to run cooler in the high country. So when precip returns late into the weekend and into early next week, precip type could be challenging once again, at least in the valleys. McKaughan && .AVIATION... Widespread clouds and deep moisture are overspreading the region this afternoon and this will lead to deteriorating conditions at all terminals through eastern Idaho. Snow is favored at SUN, IDA and DIJ while rain is favored at BYI. PIH could begin as a mix, but should eventually change over to rain based on model soundings. That being said, there is a great deal of uncertainty in regards to precip-type at KPIH and even KBYI. Do think that RA is most likely through around 09Z at these locations before a return to RASN or all SN is possible around daybreak Tuesday. We should see a brief lull in precip by midday Tuesday before the next round of precipitation moves in during the evening and into the overnight hours Wednesday with low clouds and precip expected. McKaughan && .PIH WATCHES/WARNINGS/ADVISORIES... Winter Weather Advisory until 11 PM MST this evening for IDZ051- 072>075. Winter Weather Advisory until 11 AM MST Tuesday for IDZ052-053- 057-058-060>066-068. && $$